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PubMed2005

The use of non-human primates in biological and medical research: evidence submitted by FRAME to the Academy of Medical Sciences/Medical Research Council/Royal Society/Wellcome Trust Working Group.

The Academy of Medical Sciences, the Medical Research Council, the Royal Society and the Wellcome Trust are undertaking a study into the use of non-human primates in biological and medical research. An independent working group of scientific experts, led by Sir David Weatherall, aims to produce a report summarising the findings of this study, early in 2006. The trends in primate research, and the nature and effects of recent and proposed changes in the global use of non-human primates in research, will be investigated. The associated ethical, welfare and regulatory issues, and the role and impact of the Three Rs principles of refinement, reduction and replacement will also be reviewed. As part of this study, a call for evidence was made. The evidence submitted by FRAME emphasised that the use of non-human primates for fundamental research or for regulatory testing still fails to take into account the fact that, although non-human primates are anatomically and physiologically similar to humans, they are not necessarily relevant models for studies on human disease or human physiology. FRAME continues to believe that we have a duty to ensure that these animals are not used without overwhelming evidence that they are the only suitable and relevant models for use in work of undeniable significance.

Acquired Immunodeficiency Syndrome↗
PubMed2005

Serum leptin in nonpregnant and pregnant women and in old and new world nonhuman primates.

Leptin is a hormone that is produced during mammalian pregnancy in the placental trophoblast and other tissues, including! fetal and maternal adipocytes. Synthesis of the polypeptide and the presence of its specific receptors throughout the human maternal fetoplacental unit suggest direct effects on conceptus growth and development. However, both the physiologic roles of leptin and the mechanisms regulating leptin synthesis in human pregnancy differ from those in laboratory and domestic species, necessitating the development of non-human primate research models. Therefore, we compared serum leptin concentrations in nonpregnant and pregnant women with those in both old world nonhuman primates (i.e., baboon, rhesus monkey, cynomolgus monkey) and new world nonhuman primates (i.e., squirrel monkey, titi monkey). As expected, maternal leptin levels were elevated in human and baboon pregnancies (P < 0.05 and P < 0.001, respectively). Levels in both species of old world monkeys were also greatly enhanced (P < 0.001). Although maternal serum concentrations were slightly elevated compared to nonpregnant levels in both species of new world monkeys, overall concentrations were dramatically lower than for either old world primates or humans. Results provide comparisons of serum leptin concentrations in pregnant and nonpregnant humans and baboons with those in both old and new world monkeys and further characterize these nonhuman primates as models for the investigation of leptin dynamics in pregnancy.

Animals↗
PubMed2005

Infection with transfusion-transmitted virus (TTV) in humans and other primates in Venezuela.

Tranfusion-transmitted virus (TTV), a single-stranded circular DNA virus that chronically infects humans and other animals, displays a high degree of genetic diversity and was originally thought to be associated with hepatitis. The prevalences of TTV infection among different populations of humans and non-human primates from Venezuela have now been evaluated, using serum samples and three different detection tests. All three tests were PCR-based, one involving a hemi-nested PCR and primers based on the N22 open-reading-frame-1 region (N22-PCR), another employing 55 cycles with primers from the more conserved untranslated region (UTR-PCR), and the other using a hemi-nested PCR with primers from the same region (HUTR-PCR). The overall prevalences of human infection appeared much higher with the HUTR-PCR (52%) than with the N22-PCR (13%) or the UTR-PCR (5%). When the products amplified by N22-PCR from 28 human isolates of TTV were sequenced, only two genotypes of the virus were detected. The non-human sera tested came from primates kept in a zoo in north-western Venezuela. TTV DNA was detected, by HUTR-PCR, in both of the chimpanzee sera tested but not in any of the sera from the 11 New-World primates or the other 12 Old-World primates that were investigated. The results, particularly those of the HUTR-PCR, indicate that TTV infection is common in Venezuela, especially in populations, such as many Amerindian groups, who live under poor sanitary conditions. Although TTV infection may be relatively rare among non-human primates from the New World, this will have to be investigated further, using many more samples collected throughout the Americas.

Adult↗
PubMed2005

Conservation of pregnancy-specific glycoprotein (PSG) N domains following independent expansions of the gene families in rodents and primates.

BACKGROUND: Rodent and primate pregnancy-specific glycoprotein (PSG) gene families have expanded independently from a common ancestor and are expressed virtually exclusively in placental trophoblasts. However, within each species, it is unknown whether multiple paralogs have been selected for diversification of function, or for increased dosage of monofunctional PSG. We analysed the evolution of the mouse PSG sequences, and compared them to rat, human and baboon PSGs to attempt to understand the evolution of this complex gene family. RESULTS: Phylogenetic tree analyses indicate that the primate N domains and the rodent N1 domains exhibit a higher degree of conservation than that observed in a comparison of the mouse N1 and N2 domains, or mouse N1 and N3 domains. Compared to human and baboon PSG N domain exons, mouse and rat PSG N domain exons have undergone less sequence homogenisation. The high non-synonymous substitution rates observed in the CFG face of the mouse N1 domain, within a context of overall conservation, suggests divergence of function of mouse PSGs. The rat PSG family appears to have undergone less expansion than the mouse, exhibits lower divergence rates and increased sequence homogenisation in the CFG face of the N1 domain. In contrast to most primate PSG N domains, rodent PSG N1 domains do not contain an RGD tri-peptide motif, but do contain RGD-like sequences, which are not conserved in rodent N2 and N3 domains. CONCLUSION: Relative conservation of primate N domains and rodent N1 domains suggests that, despite independent gene family expansions and structural diversification, mouse and human PSGs retain conserved functions. Human PSG gene family expansion and homogenisation suggests that evolution occurred in a concerted manner that maintains similar functions of PSGs, whilst increasing gene dosage of the family as a whole. In the mouse, gene family expansion, coupled with local diversification of the CFG face, suggests selection both for increased gene dosage and diversification of function. Partial conservation of RGD and RGD-like tri-peptides in primate and rodent N and N1 domains, respectively, supports a role for these motifs in PSG function.

Amino Acid Motifs↗
PubMed2006

Identification of the ancestral killer immunoglobulin-like receptor gene in primates.

BACKGROUND: Killer Immunoglobulin-like Receptors (KIR) are essential immuno-surveillance molecules. They are expressed on natural killer and T cells, and interact with human leukocyte antigens. KIR genes are highly polymorphic and contribute vital variability to our immune system. Numerous KIR genes, belonging to five distinct lineages, have been identified in all primates examined thus far and shown to be rapidly evolving. Since few KIR remain orthologous between species, with only one of them, KIR2DL4, shown to be common to human, apes and monkeys, the evolution of the KIR gene family in primates remains unclear. RESULTS: Using comparative analyses, we have identified the ancestral KIR lineage (provisionally named KIR3DL0) in primates. We show KIR3DL0 to be highly conserved with the identification of orthologues in human (Homo sapiens), common chimpanzee (Pan troglodytes), gorilla (Gorilla gorilla), rhesus monkey (Macaca mulatta) and common marmoset (Callithrix jacchus). We predict KIR3DL0 to encode a functional molecule in all primates by demonstrating expression in human, chimpanzee and rhesus monkey. Using the rhesus monkey as a model, we further show the expression profile to be typical of KIR by quantitative measurement of KIR3DL0 from an enriched population of natural killer cells. CONCLUSION: One reason why KIR3DL0 may have escaped discovery for so long is that, in human, it maps in between two related leukocyte immunoglobulin-like receptor clusters outside the known KIR gene cluster on Chromosome 19. Based on genomic, cDNA, expression and phylogenetic data, we report a novel lineage of immunoglobulin receptors belonging to the KIR family, which is highly conserved throughout 50 million years of primate evolution.

Amino Acid Sequence↗
PubMed2003

Darwin's legacy and the study of primate visual communication.

After Charles Darwin's The Expression of the Emotions in Man and Animals, published in 1872, we had to wait 60 years before the theme of animal expressions was picked up by another astute observer. In 1935, Nadezhda Ladygina-Kohts published a detailed comparison of the expressive behavior of a juvenile chimpanzee and of her own child. After Kohts, we had to wait until the 1960s for modern ethological analyses of primate facial and gestural communication. Again, the focus was on the chimpanzee, but ethograms on other primates appeared as well. Our understanding of the range of expressions in other primates is at present far more advanced than that in Darwin's time. A strong social component has been added: instead of focusing on the expressions per se, they are now often classified according to the social situations in which they typically occur. Initially, quantitative analyses were sequential (i.e., concerned with temporal associations between behavior patterns), and they avoided the language of emotions. I will discuss some of this early work, including my own on the communicative repertoire of the bonobo, a close relative of the chimpanzee (and ourselves). I will provide concrete examples to make the point that there is a much richer matrix of contexts possible than the common behavioral categories of aggression, sex, fear, play, and so on. Primate signaling is a form of negotiation, and previous classifications have ignored the specifics of what animals try to achieve with their exchanges. There is also increasing evidence for signal conventionalization in primates, especially the apes, in both captivity and the field. This process results in group-specific or "cultural" communication patterns.

Affect↗
PubMed1997

Developmental and functional biology of the primate fetal adrenal cortex.

The unique characteristics of the primate (particularly human) fetal adrenal were first realized in the early 1900s when its morphology was examined in detail and compared with that of other species. The unusual architecture of the human fetal adrenal cortex, with its unique and disproportionately enlarged fetal zone, its compact definitive zone, and its dramatic remodeling soon after birth captured the interest of developmental anatomists. Many detailed anatomical studies describing the morphology of the developing human fetal adrenal were reported between 1920 and 1960, and these morphological descriptions have not changed significantly. More recently, it has become clear that fetal adrenal cortical growth involves cellular hypertrophy, hyperplasia, apoptosis, and migration and is best described by the migration theory, i.e. cells proliferate in the periphery, migrate centripetally, differentiate during their migration to form the functional cortical zones, and then likely undergo apoptosis in the center of the cortex. Consistent with this model, cells of intermediate phenotype, arranged in columnar cords typical of migration, have been identified between the definitive and fetal zones. This cortical area has been referred to as the transitional zone and, based on the expression of steroidogenic enzymes, we consider it to be a functionally distinct cortical zone. Elegant experiments during the 1950s and 1960s demonstrated the central role of the primate fetal adrenal cortex in establishing the estrogenic milieu of pregnancy. Those findings were among the first indications of the function and physiological role of the human fetal adrenal cortex and led Diczfalusy and co-workers to propose the concept of the feto-placental unit, in which DHEA-S produced by the fetal adrenal cortex is used by the placenta for estrogen synthesis. Tissue and cell culture techniques, together with improved steroid assays, revealed that the fetal zone is the primary source of DHEA-S, and that its steroidogenic activity is regulated by ACTH. In recent years, function of the human and rhesus monkey fetal adrenal cortical zones has been reexamined by assessing the localization and ontogeny of steroidogenic enzyme expression. The primate fetal adrenal cortex is composed of three functionally distinct zones: 1) the fetal zone, which throughout gestation does not express 3 beta HSD but does express P450scc and P450c17 required for DHEA-S synthesis; 2) the transitional zone, which early in gestation is functionally identical to the fetal zone but late in gestation (after 25-30 weeks) expresses 3 beta HSD, P450scc, and P450c17, and therefore is the likely site of glucocorticoid synthesis, and 3) the definitive zone, which lacks P450c17 throughout gestation but late in gestation (after 22-24 weeks) expresses 3 beta HSD and P450scc, and therefore is the likely site of mineralocorticoid synthesis. Indirect evidence, based on effects of P450c21 deficiency and maternal estriol concentrations, indicate that the fetal adrenal cortex produces cortisol and DHEA-S early in gestation (6-12 weeks). However, controversy exists as to whether cortisol is produced de novo or derived from the metabolism of progesterone, as data regarding the expression of 3 beta HSD in the fetal adrenal cortex early in gestation are conflicting. During the 1960s, Liggins and colleagues demonstrated that in the sheep, cortisol secreted by the fetal adrenal cortex late in gestation regulates maturation of the fetus and initiates the cascade of events leading to parturition. Those pioneering discoveries provided insight into the mechanism underlying the timing of parturition and therefore were of particular interest to obstetricians and perinatologists confronted with the problems of preterm labor. However, although cortisol emanating from the fetal adrenal cortex promotes fetal maturation in primates as it does in sheep, its role in the regulation of primate parturition, unlike that in sheep

Adrenal Cortex↗
PubMed2005

Lineage-specific loss of function of bitter taste receptor genes in humans and nonhuman primates.

Since the process of becoming dead genes or pseudogenes (pseudogenization) is irreversible and can occur rather rapidly under certain environmental circumstances, it is one plausible determinant for characterizing species specificity. To test this evolutionary hypothesis, we analyzed the tempo and mode of duplication and pseudogenization of bitter taste receptor (T2R) genes in humans as well as in 12 nonhuman primates. The results show that primates have accumulated more pseudogenes than mice after their separation from the common ancestor and that lineage-specific pseudogenization becomes more conspicuous in humans than in nonhuman primates. Although positive selection has operated on some amino acids in extracellular domains, functional constraints against T2R genes are more relaxed in primates than in mice and this trend has culminated in the rapid deterioration of the bitter-tasting capability in humans. Since T2R molecules play an important role in avoiding generally bitter toxic and harmful substances, substantial modification of the T2R gene repertoire is likely to reflect different responses to changes in the environment and to result from species-specific food preference during primate evolution.

Animals↗
PubMed1999

Studies on karyotype evolution in higher primates in relation to human chromosome 14 and 9 by comparative mapping of immunoglobulin C epsilon genes with fluorescence in situ hybridization.

Karyotypic homologies in relation to human chromosome 14 and 9 were studied through comparative mapping of the immunoglobulin C epsilon genes in higher primates by fluorescence in situ hybridization (FISH) technique. The C epsilon genes will be suitable probes for the analysis of evolutionary rearrangements due to that the multiple recombinational events such as gene duplications and deletions have occurred repeatedly in the immunoglobulin CH gene family (IGH@) during the course of primate evolution. IGH@ locating on the terminal region of human chromosome 14 (HSA14), at band HSA14q32.33, has generated multiple pseudogenes and among subclasses of IGH@ the C epsilon genes have shown most dynamic changes with generating both truncated type (C epsilon 2) and processed type (C epsilon 3) pseudogenes. In this study, chromosomal homologies and rearrangements on HSA14 (C epsilon 1) and HSA9 (C epsilon 3) in relation to the evolutionary genesis of their primate homologous chromosomes in speciation were investigated by comparative mapping with FISH and chromosome painting (ZOO-FISH) techniques. Comparative mapping of the C epsilon 1 gene at HSA14q32.33 was carried out in seven species of nonhuman primates: common chimpanzee (PTR), pygmy chimpanzee (PPA), gorilla (GGO), orangutan (PPY), white-handed gibbon (HLA), agile gibbon (HAG), and Japanese macaque (MFU). The C epsilon 1 gene was assigned to the telomeric region of HSA14 homologues in each species, namely, PTR15q32, PPA15q32, GGO18q16, PPY15q32, HLA17qter, HAG17qter, and MFU7q29, respectively. These results suggested that HSA14 has high degree of syntenic organization with its primate homologues confirmed by ZOO-FISH. Concerning HSA9, comparative mapping of the C epsilon 3 gene at HSA9p24.2-->p24.1 was performed. The mapped positions indicated the HSA9 homologous regions detected by ZOO-FISH in each species, namely, PTR11q34, PPA11q34, GGO13q22, PPY13q16, HLA8qter, HAG8qter, and MFU14q22, respectively, suggesting that several dynamic chromosomal rearrangements including at least twice pericentric inversions have occurred during the course of hominoid evolution. The comparison of syntenic groups and painting results has provided a hypothesis of the evolutionary genesis of HSA9 and its homologues with defined breakpoints on the present chromosomes. Likewise, studies on karyotype evolution will be promoted by combining comparative mapping with ZOO-FISH that can more clearly define the chromosomal rearrangements among species.

Animals↗
PubMed1999

The role of nonhuman primates in the development of an AIDS vaccine.

Over the past decade, a substantial research investment has generated a vast body of knowledge relevant to the development of an effective AIDS vaccine. Furthermore, studies in nonhuman primates have demonstrated that a number of candidate immunogens can confer a significant degree of protection against a potentially pathogenic SIV or SHIV. Currently, there exists a robust program that supports discovery of new HIV immunogens and a proven successful program for collaborative human trials of promising vaccine candidates. However, we believe that there is a gap between discovery and clinical trials. An orderly process for screening of candidate immunogens prior to human trials would facilitate the vaccine development program. We suggest that nonhuman primates can fill this strategic gap and could accelerate vaccine development. Recognizing that there is considerable controversy about the potential usefulness of the primate models, we have attempted to set forth the relevant practical and biological issues as a series of questions for discussion. The most important biological problem is the absence of a single immune response correlate that will predict vaccine efficacy. Data from primate models indicate that such a single predictive correlate may not exist. In turn, this argues for a vaccine screening protocol that includes a pathogenic virus challenge, an approach only available in the nonhuman primate model. The further assumption is that nonprimate models can be used to predict the relative protective efficacy of diverse immunization protocols, a hypothesis that can only be tested by comparative studies yet to be conducted. A 'standard' set of virus challenges must be selected for comparison of different immunization protocols, and this effort has been initiated. At the practical level, it appears that the large number of candidate immunogens now being developed requires a screening process of the kind proposed, since it would not be practical to test all new immunogens and protocols in humans. In conclusion, it appears timely to crystallize an orderly process for the discovery, screening, and human testing of candidate AIDS vaccines, understanding that a vaccine development program should not be conducted at the expense of investigator-initiated research in the diverse disciplines that support rational vaccine design and development. The components of a rational process of vaccine development are well established and only remain to be welded into one coherent program.

AIDS Vaccines↗
PubMed1999

Nutritional modulation of aging in nonhuman primates.

Caloric restriction (CR), undernutrition without malnutrition, remains the only experimental paradigm that has been shown consistently to extend lifespan and slow aging in short-lived species. Decades of research, mostly in laboratory rodents, have shown that CR consistently extends lifespan, reduces or delays the onset of many age-related diseases and slows aging in many physiological systems. In recent years gerontologists interested in CR have focused on two unanswered questions. 1) What is the relevance of this nutritional paradigm to human aging? and 2) What biological mechanism(s) underlie the diverse effects of CR leading to a retardation of aging and disease?. To address the question of human relevance, researchers in the Intramural Research Program of the National Institute on Aging began a study of CR in nonhuman primates in the late 1980s. In addition to assessing the effects of CR on aging in primates, a major focus of this work relates to possible metabolic mechanisms of CR. A subsequent study at the University of Wisconsin Madison was initiated in the early 1990s. Certain aspects of experimental design differ between these two important ongoing investigations, but generally these studies compliment each other in many ways and have begun to provide much important data regarding the effects of CR in primates. Emerging data from these studies strongly support that physiological responses to CR in monkeys parallel the extensive findings reported in rodents. Lifespan data will not be available for several years, however, the remarkable consistency with rodent studies, in which lifespan extension is documented extensively, strengthens the possibility that CR will also extend lifespan in primates, perhaps including humans. This review summarizes the major findings from the primate CR studies after over a decade of research in this model.

Aging↗
PubMed2005

Nonhuman primates are relevant models for research in hematology, immunology and virology.

Nonhuman primates have been used for biomedical research for several decades. They have proved to be models that are relevant to humans because of the high level of gene homology which underlies physiological and biochemical similarities. The similarity of monkeys to humans has been used to investigate pathophysiological mechanisms in hematology, immunology and virology. New therapeutic procedures can be assessed in primates by using materials, in particular pharmacological reagents, and methods designed for humans. The relevance of these models also relies on the use of species-specific pathogens and the availability of recombinant, homologous cytokines. The introduction of more and more sophisticated cell and gene therapy protocols in hematopoietic cell transplantation and immunotherapy requires the development of preclinical trials similar to clinical settings. For several decades now, baboons and cynomolgus/rhesus monkeys have been the most useful primate models in experimental hematology, and this has contributed to numerous therapeutic advances. Primate models of AIDS have been developed to study the pathogenesis, transmission and immune responses to infection, and to test vaccines and drugs. Primate research should be restricted in quantity, and mainly designed with the aim of removing uncertainty as to the safety and clinical benefit to the patient, of new biomedical protocols.

Allergy and Immunology↗
PubMedDate not supplied

Antiretroviral drug studies in nonhuman primates: a valid animal model for innovative drug efficacy and pathogenesis experiments.

Several nonhuman primate models are used in HIV and AIDS research. In contrast to HIV-1 infection of chimpanzees, infection of macaque species with simian immunodeficiency virus (SIV) isolates results in a disease (simian AIDS) that shares many similarities with HIV infection and AIDS in humans. Although each animal model has its limitations and can never completely mimic HIV infection of humans, a carefully designed study allows experimental approaches, such as the control of certain variables, that are not feasible in humans, but that are often the most direct way to gain better insights in disease pathogenesis and provide proof-of-concept for novel intervention strategies. In the early days of the HIV pandemic, nonhuman primate models played a relatively minor role in the anti-HIV drug development process. During the past decade, however, the development of better virologic and immunologic assays, a better understanding of disease pathogenesis, and the availability of better drugs have made these animal models more practical for drug studies. In particular, nonhuman primate models have played an important role in demonstrating: (i) preclinical efficacy of novel drugs such as tenofovir; (ii) the benefits of chemoprophylaxis, early treatment and immunotherapeutic strategies; (iii) the virulence and clinical significance of drug-resistant viral mutants; and (iv) the role of antiviral immune responses during drug therapy. Comparison of results obtained in primate models with those observed in human studies will lead to further validation and improvement of these animal models. Accordingly, well-designed drug studies in nonhuman primates can continue to provide a solid scientific basis to advance our scientific knowledge and to guide future clinical trials.

Animals↗
PubMed1992

Mhc-DQB repertoire variation in hominoid and Old World primate species.

Comparison of 87 distinct Mhc-DQB sequences, obtained from 13 primate species, demonstrates that five out of eight trans-species Mhc-DQB allele lineages are at least 30 million years old and predate divergence of hominoid and Old World primate species. One lineage may be much older because its members are not only traced back in higher primates, but also are present in a New World primate species. Comparing Mhc-DQB repertoire variation in distinct species, allows one to pinpoint when certain polymorphisms were lost or gained in primate evolution. Heterogeneity observed among members of trans-species Mhc-DQB allele lineages can be explained in major part by point mutations, whereas intraexonic crossing-over is a potent mechanism in generating new allele lineages. The stability of Mhc-DQB polymorphisms is influenced by selective forces because distinct allele lineages appear to have accumulated nucleotide substitutions and amino acid replacements at different rates.

Alleles↗
PubMed1988

Enamel structure in primates: a review of scanning electron microscope studies.

Comparative studies of dental enamel microstructure have involved three main areas of enquiry, with structural features having been investigated in relation to developmental mechanisms, function and/or phylogeny. The phylogenetic, or taxonomic aspect has been emphasized in the majority of studies involving the Order Primates, where efforts have focused upon attempts to recognise structural differences among various hierarchical groups. Studies of primate enamel microstructure by SEM are reviewed here, with emphasis on what has been learned concerning the most suitable preparative techniques that can be employed, and with particular emphasis to the relevance of enamel microstructure in taxonomic analyses of living and fossil primates. No one technique of enamel preparation can be held to be the most suitable for all types of material (e.g., fresh developing, wet mature, dry mature, and fossil enamel) but experience to date allows us to make some recommendations. Two aspects of enamel structure have been shown to possess considerable potential in taxonomic analyses: the enamel prism packing patterns, and the enamel formation rates as documented from prism cross-striation repeat intervals. Although the distribution of enamel prism packing patterns among primates suggests considerable homoplasy of this character, this feature does have considerable taxonomic interest at certain hierarchical levels in Primates. The study of rates of enamel secretion coupled with analyses of enamel thickness has considerable potential in resolving taxonomic and phylogenetic questions.

Animals↗
PubMed1995

Control of lipolysis in intra-abdominal fat cells of nonhuman primates: comparison with humans.

The mechanisms that control lipolysis in intra-abdominal fat cells from various primate species, the marmoset (Callithrix jacchus), the baboon (Papio papio), and the macaque (Macaca fascicularis), were compared to those of human intraabdominal fat cells. Selective beta 1- or beta 2-adrenoceptor agonists induced lipolysis in all species. Selective beta 3-agonists (BRL 37344, CL 316243, and SR 58611) acted as partial agonists in marmoset but were inefficient in other primates, including humans. alpha 2-Adrenoceptor number ([3H]RX 8210002 binding) equalized (baboon) or exceeded (other primates) beta 1/beta 2-adrenoceptors ([3H]CGP 12177 binding). Baboon fat cell membranes expressed similar amounts of coupled beta- and alpha 2-adrenoceptors. In all species, norepinephrine- or epinephrine-induced lipolysis did not reach the lipolytic effect of isoproterenol but their effects were enhanced after alpha 2-adrenoceptor blockade. N6-phenylisopropyladenosine (PIA) induced a full antilipolytic effect in baboon, macaque, and human adipocytes through adenosine receptors ([3H]DPCPX binding). Peptide YY (PYY) weakly inhibited lipolysis in baboon. Adrenocorticotropic hormone (ACTH) was inactive whereas parathyroid hormone (PTH) partially stimulated lipolysis in primates. Histamine was partially lipolytic in marmoset only. This study emphasizes the similarities of the mechanisms controlling the lipolysis in nonhuman primate and in human adipocytes and suggests that the baboon and the macaque should provide unique models for the study of the regulation of lipolysis.

Abdomen↗
PubMed1993

Blood group A and B glycosyltransferases in nonhuman primate plasma.

The products of the blood group A and B genes, alpha-3-N-acetyl-D-galactosaminyltransferase (A-transferase) and alpha-3-D-galactosyltransferase (B-transferase) in 83 plasma samples of 24 species of nonhuman primates were investigated by enzymatic conversion of human group O red cells into A or B active cells. The conversions were demonstrated by the anti-A and anti-B agglutinability of the red cells. The plasma from group A and B anthropoid apes converted untreated group O human red cells into A and B active cells in the presence of UDP-N-acetyl-D-galactosamine and UDP-D-galactose, respectively. When papain-treated O red cells were used as an acceptor, A and B conversions by plasma glycosyltransferases of prosimians, New and Old World monkeys were detected. Most of the plasma from nonhuman primates contained A- or/and B-transferase activities that correspond to the A and B antigens expressed in the red cells. The A and B enzyme activities from nonhuman primates were almost equivalent to those from human A and B subgroups or variants. H antigen in the red cells of pig-tailed monkeys could be converted to A and B active ones by using plasma samples from man and nonhuman primates as enzyme sources. The optimal pH of A-transferases from Old World monkeys and human group A2 were 7.4 and 7.6, and from anthropoid apes and human group A1 they were 6.6 and 6.4, respectively. The pH optima of B-transferases from nonhuman primates and man distributed at 6.2-6.5.

ABO Blood-Group System↗
PubMed1998

Horizontal cell connections with short wavelength-sensitive cones in the retina: a comparison between New World and Old World primates.

Recent studies in the Old World macaque monkey have shown that the two horizontal cell types H1 and H2 differ with respect to their connections to short wavelength-sensitive (SWS) cones. We wanted to establish whether this pattern of connectivity is common to all primates. The connections of horizontal cells with SWS cones were studied in the retinas of two species of New World (marmoset and tamarin) and two species of Old World (orangutan and chimpanzee) primates by using a double-labelling technique. Horizontal cells were labelled with DiI and then photoconverted; SWS cones were labelled immunocytochemically. The marmoset shows a sex-linked polymorphism of colour vision: All males are dichromats, whereas most females are trichromats. In contrast, Old World primates are usually trichromats. Our results show that the horizontal cells of both New World and Old World primates have a comparable pattern of connectivity with SWS cones and thus indicate that the wiring of horizontal cells with SWS cones does not differ between dichromats and trichromats and is common to all primates. The H1 cells make no or only sparse contact with SWS cones. In marmoset, H1 cells have on average 0.8% of their dendritic terminals at SWS cones. The H2 cells contact all SWS cones in their dendritic field. In marmoset, H2 cells have on average 11.8% of their dendritic terminals at SWS cones. The axon of H2 cells contacts SWS cones but presumably also contacts other cones.

Animals↗